CVS11 Peripheral Arterial and Venous Disease-Evita Flashcards
into which categories can lower limb veins be divided into?
superficial
deep
define superficial veins
in subcutaneous fat
define deep veins
within muscle
in which direction is blood flow in veins?
superficial to deep
what are perforating veins?
veins which run superficial to deep
how does pressure within a muscle compartment rise?
muscles contract, causing fascia to be drawn in tight, causing pressure within the compartment to rise
what controls the movement of blood in veins back to the heart?
changing pressures within the compartment in which the vein resides
muscle contraction causes pressure to rise, so blood is pushed back to the heart
what is the one constant vein in the body and where is it found?
long saphenous vein
seen anterior to the medial malleolus
define varicose veins
twisted or lengthened veins
describe the pathophysiology of varicose veins
vein wall is weak
there is dilatation and separation of valve cusps
valve becomes incompetent
what are the symptoms of varicose veins?
- heaviness
- tension
- aching
- Itching
what are the complications of varicose veins?
- haemorrhage
- thrombophlebitis
- oedema
- skin pigmentation
- varicose eczema
- lipodermatoslcerosis
- venous ulceration
define thrombophlebitis
inflammation if the vein wall, associated with thrombosis
painful
define lipodermatosclerosis
inflammation of subcutaneous fat with skin hardening
what is venous hypertension a result of?
calf muscle pump failure
what are the causes of calf muscle failure?
- immobility
- obesity
- reduced leg movement
- deep vein incompetence (born with it)
- volume overlaid-superficial vein incompetence
what does calf muscle failure cause?
venous hypertension
what is the commonest cause of arterial thrombosis?
changes in the lining of the vessel wall
what is the most common cause of venous thrombosis?
changes in the flow of blood (i.e. stasis)
what is the difference in the composition of arterial thrombi vs venous thrombi?
arterial thrombi are platelet-rich
venous thrombi are fibrin-rich
where does deep vein thrombosis most commonly occur?
deep calf muscles
what are the clinical features of DVT?
- pain
- swelling
- blue-red skin discolouration
- calf tenderness
- muscle induration (mass)
- skin warmth
- oedema
- pyrexia
why can surgery increase the risk of DVT?
- immobility prior to and after surgery
- no calf muscle pump during surgery
- surgery causes a pro-thrombotic state as it is traumatic
what is the fatal consequence of DVT?
pulmonary embolism
when does development of collateral circulation occur?
when there is chronic stenosis of a vessel, allowing enough time for angiogenesis
what is the commonest cause of acute limb ischaemia?
embolism from heart or abdominal aortic aneurysm
trauma
within what time period must acute limb ischaemia be reversed for the limb to recover?
6 hours
why must the limb be amputated if the patient has acute limb ischaemia that has not been reversed in time?
the patient will die if not amputated as the dead tissue releases its intracellular potassium, causing hyperkalaemia
what are the signs/symptoms of acute ischaemia?
pain paralysis paraesthesia pallor perishing cold pulseless (6 P's)
what is the appearance of a limb that has undergone acute limb ischaemia and is no longer viable?
fixed mottling patchy blue (cyanosis) pressing=will not blanch
define claudication
pain in muscles of the lower limb elicited by walking/exercise
what is chronic limb ischaemia?
gradual loss of blood supply to the lower limb
what do patients with chronic limb ischaemia present with?
claudication as condition progresses: pain at rest arterial ulcers gangrene
which artery is most commonly diseased in chronic peripheral arterial disease?
superficial femoral artery
which muscles are most commonly affected by chronic peripheral arterial disease?
calf muscles (as they’re supplied by the superficial femoral artery)
what are the two pedal pulses that can be felt?
dorsalis pedis artery pulse
posterior tibial artery pulse
where is the dorsals pedis pulse felt?
lateral to extensor hallucis longus tendon
where is the posterior tibial pulse felt?
behind the medial malleolus
describe the pain in the foot that is present due to critical limb ischaemia
pain in the foot that comes on when the patient goes to bed and is relieved by hanging the foot out of the bed
what can critical limb ischaemia progress to?
gangrene and/or ulceration
